This is a regular expression to match completely each line of your file.
^([0-9]+) => Match the year (actually any number) at the beginning of the line and hold in a group (referred later as group #1 or $1)
\s* => Match any following whitespaces
([a-zA-Z]+) => Match the make (actually group of lower and upper case alphabets) following the whitespace and hold in the next group (referred later as group #2 or $2)
\s* => Match any following whitespaces
(.*)$ => Match the model that is more than a word (actually all the characters following the previous whitespace) until the end of line and hold in the next group (referred later as group #3 or $3)